How do you make locale sensitive classes accept your own resourceBundle classes?

This is a design of the locale-sensitive classes. However, most locale-sensitive classes like NumberFormat or DecimalFormat allow you set number format patterns and symbols of your own. So, even though you can not provide your own ResourceBundle for these classes, you can read patterns and symbols from your own bundles and apply them.
See the applyPattern() and getDecimalFormatSymbols() methods in DecimalFormat to start you off.

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